feat: add helm chart release workflow

.github/workflows/karpenter-chart-release.yaml

@@ -0,0 +1,81 @@
+name: Release Karpenter Helm Chart
+
+on:
+  push:
+    tags:
+      - 'karpenter-chart/v*'
+  workflow_dispatch:
+    inputs:
+      version:
+        description: 'Chart version override (e.g. 0.2.0). Leave empty to use Chart.yaml version.'
+        required: false
+        type: string
+
+env:
+  REGISTRY: ghcr.io
+  CHART_NAME: karpenter
+
+jobs:
+  release:
+    runs-on: ubuntu-latest
+    permissions:
+      contents: write
+      packages: write
+
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Set up Helm
+        uses: azure/setup-helm@v4
+        with:
+          version: v3.17.0
+
+      - name: Determine chart version
+        id: version
+        run: |
+          if [[ -n "${{ inputs.version }}" ]]; then
+            VERSION="${{ inputs.version }}"
+          elif [[ "$GITHUB_REF" == refs/tags/karpenter-chart/v* ]]; then
+            VERSION="${GITHUB_REF#refs/tags/karpenter-chart/v}"
+          else
+            VERSION=$(grep '^version:' karpenter/charts/karpenter/Chart.yaml | awk '{print $2}')
+          fi
+          echo "version=${VERSION}" >> "$GITHUB_OUTPUT"
+          echo "Chart version: ${VERSION}"
+
+      - name: Log in to GHCR
+        run: |
+          echo "${{ secrets.GITHUB_TOKEN }}" | helm registry login ${{ env.REGISTRY }} \
+            --username ${{ github.actor }} \
+            --password-stdin
+
+      - name: Package and push Helm chart
+        run: |
+          karpenter/hack/release-chart.sh \
+            --version "${{ steps.version.outputs.version }}" \
+            --registry "oci://${{ env.REGISTRY }}/${{ github.repository }}/charts" \
+            --push
+
+      - name: Create GitHub Release
+        if: startsWith(github.ref, 'refs/tags/karpenter-chart/v')
+        uses: softprops/action-gh-release@v2
+        with:
+          name: "Karpenter Helm Chart v${{ steps.version.outputs.version }}"
+          body: |
+            ## Karpenter Helm Chart v${{ steps.version.outputs.version }}
+
+            ### Install from OCI registry
+            ```bash
+            helm install karpenter oci://${{ env.REGISTRY }}/${{ github.repository }}/charts/${{ env.CHART_NAME }} \
+              --version ${{ steps.version.outputs.version }} \
+              --namespace kube-system
+            ```
+
+            ### Install from downloaded archive
+            ```bash
+            helm install karpenter ./${{ env.CHART_NAME }}-${{ steps.version.outputs.version }}.tgz \
+              --namespace kube-system
+            ```
+          files: .helm-packages/${{ env.CHART_NAME }}-${{ steps.version.outputs.version }}.tgz
+          fail_on_unmatched_files: true

.gitignore

@@ -432,4 +432,7 @@ dist/
 
 .env
 .kube
-*.kubeconfig
+*.kubeconfig
+
+# Helm chart packaging output
+.helm-packages/

karpenter/Makefile

@@ -150,6 +150,20 @@ build-installer: manifests generate kustomize ## Generate a consolidated YAML wi
 	mkdir -p dist
 	$(KUSTOMIZE) build config/default > dist/install.yaml
 
+##@ Helm Chart
+
+.PHONY: helm-lint
+helm-lint: ## Lint the Karpenter Helm chart.
+	helm lint charts/karpenter
+
+.PHONY: helm-package
+helm-package: ## Lint and package the Karpenter Helm chart into a .tgz archive.
+	hack/release-chart.sh
+
+.PHONY: helm-push
+helm-push: ## Lint, package, and push the Karpenter Helm chart to an OCI registry. Requires HELM_REGISTRY (e.g. oci://ghcr.io/azure/aks-flex/charts).
+	hack/release-chart.sh --registry $(HELM_REGISTRY) --push
+
 ##@ Deployment
 
 ifndef ignore-not-found

karpenter/hack/release-chart.sh

@@ -0,0 +1,92 @@
+#!/usr/bin/env bash
+# Build, package, and optionally push the Karpenter Helm chart.
+#
+# Usage:
+#   ./hack/release-chart.sh [options]
+#
+# Options:
+#   --version VERSION   Override chart version (default: read from Chart.yaml)
+#   --registry URI      OCI registry to push to (e.g. oci://ghcr.io/azure/aks-flex/charts)
+#   --output DIR        Output directory for the .tgz package (default: .helm-packages)
+#   --push              Push the chart to the OCI registry after packaging
+#   --help              Show this help message
+#
+# Examples:
+#   # Lint and package only (local dev)
+#   ./hack/release-chart.sh
+#
+#   # Package with a specific version
+#   ./hack/release-chart.sh --version 0.2.0
+#
+#   # Package and push to GHCR
+#   ./hack/release-chart.sh --version 0.2.0 --registry oci://ghcr.io/azure/aks-flex/charts --push
+
+set -euo pipefail
+
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+CHART_DIR="${SCRIPT_DIR}/../charts/karpenter"
+
+# Defaults
+VERSION=""
+REGISTRY=""
+OUTPUT_DIR="${SCRIPT_DIR}/../../.helm-packages"
+PUSH=false
+
+usage() {
+  sed -n '2,/^$/s/^# \{0,1\}//p' "$0"
+  exit 0
+}
+
+while [[ $# -gt 0 ]]; do
+  case "$1" in
+    --version)  VERSION="$2";   shift 2 ;;
+    --registry) REGISTRY="$2";  shift 2 ;;
+    --output)   OUTPUT_DIR="$2"; shift 2 ;;
+    --push)     PUSH=true;      shift ;;
+    --help|-h)  usage ;;
+    *) echo "Unknown option: $1" >&2; usage ;;
+  esac
+done
+
+# ---------------------------------------------------------------------------
+# Resolve chart version
+# ---------------------------------------------------------------------------
+if [[ -z "$VERSION" ]]; then
+  VERSION=$(grep '^version:' "$CHART_DIR/Chart.yaml" | awk '{print $2}')
+fi
+echo "Chart version: ${VERSION}"
+
+# ---------------------------------------------------------------------------
+# Step 1: Lint
+# ---------------------------------------------------------------------------
+echo "==> Linting chart..."
+helm lint "$CHART_DIR"
+
+# ---------------------------------------------------------------------------
+# Step 2: Package
+# ---------------------------------------------------------------------------
+mkdir -p "$OUTPUT_DIR"
+echo "==> Packaging chart..."
+helm package "$CHART_DIR" --version "$VERSION" --destination "$OUTPUT_DIR"
+
+CHART_PACKAGE="${OUTPUT_DIR}/karpenter-${VERSION}.tgz"
+if [[ ! -f "$CHART_PACKAGE" ]]; then
+  echo "Error: expected package not found: $CHART_PACKAGE" >&2
+  exit 1
+fi
+echo "Package created: ${CHART_PACKAGE}"
+
+# ---------------------------------------------------------------------------
+# Step 3: Push (optional)
+# ---------------------------------------------------------------------------
+if [[ "$PUSH" == true ]]; then
+  if [[ -z "$REGISTRY" ]]; then
+    echo "Error: --registry is required when --push is set" >&2
+    exit 1
+  fi
+  echo "==> Pushing chart to ${REGISTRY}..."
+  helm push "$CHART_PACKAGE" "$REGISTRY"
+  echo "Chart pushed successfully."
+fi
+
+echo "Done."